Guitars contain a jack, also referred to as a military phone jack, into which electrical leads are plugged. To ensure good connection of the lead into the jack, the jack should be securely lodged on the guitar. Securing of the jack to the guitar is typically accomplished through use of a jam nut. Wrenches and pliers currently in use to tighten the jam nut suffer from the disadvantage of causing the jack to spin during the tightening, which can then lead to tearing and otherwise damaging the wires attached to jack. Thus, there is a need for a tool for tightening military phone jacks which does not cause spinning of the jack during tightening of the jam nut.